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1.
J Appl Microbiol ; 135(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38419296

RESUMEN

AIM: This study aimed to isolate, endophytic Streptomyces sp. MSARE05 isolated from root of a peanut (Arachis hypogaea) inhibits the growth of other bacteria. The research focused on characterizing the strain and the antimicrobial compound. METHODS AND RESULTS: The surface-sterilized peanut roots were used to isolate the endophytic bacterium Streptomyces sp. MSARE05. A small-scale fermentation was done to get the antimicrobial compound SM05 produced in highest amount in ISP-2 medium (pH 7) for 7 days at 30°C in shaking (180 rpm) condition. Extraction, purification, and chemical analysis of the antibacterial component revealed a novel class of antibiotics with a 485.54 Dalton molecular weight. The MIC was 0.4-0.8 µg ml-1 against the tested pathogens. It also inhibits multidrug-resistant (MDR) pathogens and Mycobacterium with 0.8-3.2 µg ml-1 MIC. SM05 was found to disrupt cell membrane of target pathogen as evident by significant leakage of intracellular proteins and nucleic acids. It showed synergistic activity with ampicillin, chloramphenicol, streptomycin, and kanamycin. CONCLUSIONS: The new-class antimicrobial SM05 consisting naphthalene core moiety was effective against drug-resistant pathogens but non-cytotoxic to human cells. This study underscores the significance of endophytic Streptomyces as a source of innovative antibiotics, contributing to the ongoing efforts to combat antibiotic resistance.


Asunto(s)
Antiinfecciosos , Streptomyces , Humanos , Streptomyces/metabolismo , Arachis , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Esterilización , Raíces de Plantas/microbiología
2.
Org Biomol Chem ; 21(46): 9270-9274, 2023 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-37970956

RESUMEN

Nitric oxide (NO) plays a key role in regulating plant growth, enhances nutrient uptake, and activates disease and stress tolerance mechanisms in most plants. NO is marked as a potential tool for improving the yield and quality of horticultural crop species. Research on NO in plant species can provide an abundance of valuable information regarding this. Hence, we have prepared a simple chemosensor (NPO) for the detection of endogenous NO in chickpea saplings. NPO selectively interacts with NO as determined through a chemodosimetric method to clearly show both the colorimetric and fluorometric changes. After the interaction with NO, the colorless NPO turns yellow as observed by the naked eye and shows bright cyan-blue fluorescence under a UV lamp. The 1 : 1 stoichiometric ratio between NPO and NO is determined from Job's plot resulting in a stable diazeniumdiolate product. The interaction mechanism is well established by absorption, fluorescence titration, NMR titration, HRMS, and DFT calculations. This method has successfully been employed in the plant's root and stem systems to label NO. Confocal microscopy images might help us to understand the endogenous NO generation and the mechanism that happens inside plant tissues.


Asunto(s)
Óxido Nítrico , Células Vegetales , Espectrometría de Fluorescencia/métodos , Fluorometría
3.
Environ Sci Process Impacts ; 25(7): 1144-1149, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37345355

RESUMEN

Sensing of gaseous environment pollutants and health hazards is in demand these days and in this regard, lethal phosgene has emerged as a leading entrant. In this contribution, we have successfully developed a facile chemodosimeter (ANO) based on an anthracene fluorophore and oxime recognition site with an interesting mechanism to sense lethal phosgene evolved from bleaching powder, a very popular disinfectant and sanitizer. The ANO probe is highly competent in recognizing deadly phosgene in solution and in the gaseous phase with a detection limit in the nanomolar range (1.52 nM). The sensing mechanism is confirmed by UV-vis, emission spectroscopy, mass spectrometry, and computational studies.


Asunto(s)
Fosgeno , Fosgeno/análisis , Fosgeno/química , Análisis Costo-Beneficio , Espectrometría de Fluorescencia/métodos , Gases/química , Colorantes Fluorescentes/química
4.
J Photochem Photobiol B ; 245: 112747, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37331157

RESUMEN

Cysteine is directly associated with a wide range of biological processes. Besides its essential role in protein synthesis, cysteine undergoes a variety of post-translational modifications which modulate several physiological processes. Dysregulated cysteine metabolism is associated with several neurodegenerative disorders. Accordingly, restoring cysteine balance has therapeutic benefits. It is therefore essential to detect the presence of endogenous free cysteine in order to understand different physiological modes of action inside the cell. Here, a carbazole-pyridoxal conjugate system (CPLC) has been developed to detect endogenous free cysteine in the liver and kidney of an adult zebrafish. In consequence, we have also determined the fluorescence intensity statistics of zebrafish kidney and liver images. CPLC interacts in a very fascinating way with two cysteine molecules through chemodosimetric and chemosensing approaches which are conclusively proved by different spectroscopic analyses (UV-vis, fluorescence, NMR) and theoretical calculations (DFT). The detection limit of CPLC towards cysteine is 0.20 µM. Moreover, this preliminary experiment has been done using HuH-7 cell line to check the permeability of CPLC, interaction with cysteine intracellularly, and assessment of the toxicity of CPLC, if any, before performing details in-vivo experiments in zebrafish model.


Asunto(s)
Colorantes Fluorescentes , Pez Cebra , Animales , Fluorescencia , Colorantes Fluorescentes/química , Cisteína/análisis , Hígado , Espectrometría de Fluorescencia/métodos , Riñón
5.
Plant Physiol Biochem ; 198: 107693, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37060869

RESUMEN

Chromium (Cr) contamination of soil and water poses serious threats to agricultural crop production. MicroRNAs (miRNAs) are conserved, non-coding small RNAs that play pivotal roles in plant growth, development and stress responses through fine-tuning of post-transcriptional gene expression. To better understand the molecular circuit of Cr-responsive miRNAs, two sRNA libraries were prepared from control and Cr (VI) [100 ppm] exposed maize roots. Using deep sequencing, we identified 80 known (1 up and 79 down) and 18 downregulated novel miRNAs from Cr (VI) challenged roots. Gene ontology (GO) analysis reveals that predicted target genes of Cr (VI) responsive miRNAs are potentially involved in diverse cellular and biological processes including plant growth and development (miR159c, miR164d, miR319b-3p and zma_25.145), redox homeostasis (miR528-5p, miR396a-5p and zma_9.132), heavy metal uptake and detoxification (miR159f-5p, 164e-5p, miR408a, miR444f and zma_2.127), signal transduction (miR159f, miR160a-5p, miR393a-5p, miR408-5p and zma_43.158), cell signalling (miR156j, 159c-5p, miR166c-5p and miR398b). Higher accumulation of Cr in maize roots might be due to upregulation of ABC transporter G family member 29 targeted by miR444f. Instead of isolated increase in SOD expression, significant decline in GSH:GSSH ratio and histochemical staining strongly suggest Cr (VI) stress mediated disruption of ROS scavenging machinery thus unbalancing normal cellular homeostasis. Moreover, miR159c-mediated enhanced expression of GAMYB might be a reason for impaired root growth under Cr (VI) stress. In a nutshell, the present microRNAomic study sheds light on the miRNA-target gene regulatory network involved in adaptive responses of maize seedlings to Cr (VI) stress.


Asunto(s)
MicroARNs , Zea mays , Zea mays/metabolismo , Cromo , MicroARNs/genética , MicroARNs/metabolismo , Redes Reguladoras de Genes , Regulación hacia Arriba , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica
6.
Org Biomol Chem ; 21(5): 981-986, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36562275

RESUMEN

A new fluorescent chemosensor (NAN), fabricated by integrating 2-hydroxy naphthaldehyde and 1,8-naphthalic anhydride, shows high affinity for aluminium over other bio-relevant metal ions. The probe solution rapidly switched from non-fluorescent to bright blue fluorescence upon the addition of Al3+ under a UV-lamp, possessing a remarkably low detection limit of 33 nM. The interaction mechanism between the metal ion and NAN has been well established by a number of techniques such as absorbance, fluorescence, and 1H NMR titration and verified by detailed theoretical calculations as well. To show the practical efficacy of our synthesized probe NAN we have employed it to recognize Al3+ only by using a simple paper strip and estimate the concentration of Al3+ ions in various pharmaceutical drugs and supplements as they are some of the major sources of aluminium accumulation in the human body resulting in various neurodegenerative disorders, especially Alzheimer's disease.


Asunto(s)
Aluminio , Metales , Humanos , Aluminio/química , Iones/química , Fluorescencia , Preparaciones Farmacéuticas , Colorantes Fluorescentes/química , Espectrometría de Fluorescencia/métodos
7.
Sci Rep ; 12(1): 2305, 2022 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-35145184

RESUMEN

An easily accessible colorimetric probe, a carbazole-naphthaldehyde conjugate (CNP), was successfully prepared for the selective and sensitive recognition of Sn(II) in different commercially-available toothpaste and mouth wash samples. The binding mechanism of CNP for Sn2+ was confirmed by UV-Vis, 1H, and 13C NMR titrations. The proposed sensing mechanism was supported by quantum chemical calculations. Selective detection of Sn(II) in the nanomolar range (85 nM), among other interfering metal ions, makes it exclusive. Moreover, Sn2+ can be detected with a simple paper strip from toothpaste, which makes this method handy and easily accessible. The potential application of this system for monitoring Sn2+ can be used as an expedient tool for environmental and industrial purposes.

8.
Environ Sci Process Impacts ; 23(9): 1308-1315, 2021 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-34286814

RESUMEN

A naphthaldehyde-pyridoxal conjugated chemodosimeter (NPLC) was developed and employed for the sensitive and selective detection and estimation of cyanide in common water hyacinth (Eichhornia crassipes), a free floating macrophyte used in the phytoremediation process since ancient times. The non-fluorescent nature of the probe NPLC, directed by the possibility of excited state intramolecular proton transfer process (ESIPT), was promptly changed due to CN- induced di-deprotonation of the probe. The naked eye color change and turn on vivid fluorescent color of NPLC was attributed to the inhibition of the ESIPT mechanism in the deprotonated NPLC (NPLC-D). The selective detection of cyanide ion in the nanomolar range (81 nM), among other interfering anions, makes it exclusive. The involvement of the probe in a chemodosimetric fashion toward cyanide was elucidated by experimental and computational studies.


Asunto(s)
Eichhornia , Contaminantes Químicos del Agua , Biodegradación Ambiental , Cianuros/análisis , Agua
9.
Bioorg Med Chem Lett ; 49: 128287, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34311088

RESUMEN

A new strategy has been developed for selective estimation of toxic Formaldehyde (FA) in storage fish samples by a simple chemosensor (BNDI) based on naphthalene diimide core in aqueous medium at neutral pH. The rapid "lightning-up" fluorescence feature of BNDI has been implied to detect and estimate aqueous FA selectively at very low concentration. The chemosensing properties of BNDI with aqueous FA have been established through a unique interaction pattern which is proven by different spectroscopic and theoretical analysis.


Asunto(s)
Colorantes Fluorescentes/química , Formaldehído/análisis , Naftalimidas/química , Animales , Peces , Contaminación de Alimentos/análisis , Formaldehído/química , Enlace de Hidrógeno , Límite de Detección , Alimentos Marinos/análisis , Espectrometría de Fluorescencia , Agua/química
10.
Econ Model ; 94: 386-400, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33110283

RESUMEN

In examining the role of institutions in resisting corruption and its impact on growth, most studies concentrate on the aggregate level and conclude that sound institutions enhance growth. We focus instead on varying dimensions of heterogeneous institutions in the presence of corruption and their interactive effect on stock returns in four emerging economies: Brazil, Russia, India, and China (BRIC). We pay particular attention to democratic accountability, bureaucratic quality, and law and order. Using monthly data for the first time in this literature, we find that corruption and other weaker institutions lower stock returns during the period 1995-2014. However, interaction effects show interesting mixed results: Bureaucratic quality can mitigate the ill effects of corruption and increase returns by reducing red tape, whereas corruption distorts law and order and lowers stock returns. Our findings suggest that policies to enhance bureaucratic efficiency can abate the adverse effects of corruption, but a restrictive law and order environment tends to lower stock returns.

11.
Org Biomol Chem ; 18(34): 6716-6723, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32820796

RESUMEN

An innovative fluorescein appended naphthalene diimide based probe (FANDI) has been prepared and characterized to selectively recognize hypochlorite or ClO- ions in the presence of other reactive oxygen species (ROS) and biorelevant ions, using a unique chemodosimetric method. Hypochlorite induced oxidation can efficiently alter the initial photophysical properties of FANDI and shows an easily detectable "turn on" green fluorescence. The chemodosimeter FANDI can efficiently detect exogenous as well as endogenous ClO- ions in RAW 264.7 cells (macrophages) and zebrafish embryos (Danio rerio) which further ensures the high potential, easy cell permeability and photostability of FANDI and makes it worth exploring in the future.


Asunto(s)
Ácido Hipocloroso
12.
Anal Bioanal Chem ; 411(23): 6203-6212, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31300856

RESUMEN

Cysteine is a crucial amino acid, found in a huge amount in protein-rich foods. We focused our research to determine the amount of free cysteine consumed highly in foods such as pork, beef, poultry, eggs, dairy, red peppers, soybeans, broccoli, brussels sprouts, oats, and wheat germs. A newly designed carbazole-pyridine-based fluorescent probe (CPI) has been introduced for quantitative estimation of cysteine (Cys) with a "turn on" fluorescence in some popular processed food samples chosen from our daily diet. CPI shows both naked eye and UV-visible color changes upon interaction with cysteine. The binding approach between CPI and Cys at biological pH has been thoroughly explored by UV-visible and fluorescence spectroscopy. From Job's plot analysis, 1:1 stoichiometric reaction between CPI and Cys is observed with a detection limit of 3.8 µM. NMR, ESI mass spectrometry, and time-dependent density functional theory (TD-DFT) study enlightens the formation of more stable product CPI-Cys. The "turn on" response of the probe CPI occurs due to the interruption of intra-molecular charge transfer (ICT) process upon reacting with cysteine. Moreover, CPI is a very stable, cost-effective compound and exhibits excellent real-time selectivity towards Cys over all other comparative biorelevant analytes. Interestingly, our proposed method is much advantageous as it is able to estimate cysteine predominantly by screening out other comparative biocomponents found in different protein-rich foods.


Asunto(s)
Carbazoles/química , Cisteína/análisis , Colorantes Fluorescentes/química , Análisis de los Alimentos/métodos , Piridinas/química , Límite de Detección , Modelos Moleculares , Espectrometría de Fluorescencia/métodos
13.
Fish Physiol Biochem ; 43(1): 77-88, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27492114

RESUMEN

The obligatory air-breathing mud eel (Monopterus cuchia) is frequently being challenged with high environmental ammonia (HEA) exposure in its natural habitats. The present study investigated the possible induction of heat shock protein 70 and 90 (hsp70, hsc70, hsp90α and hsp90ß) genes and more expression of Hsp70 and Hsp90 proteins under ammonia stress in different tissues of the mud eel after exposure to HEA (50 mM NH4Cl) for 14 days. HEA resulted in significant accumulation of toxic ammonia in different body tissues and plasma, which was accompanied with the stimulation of oxidative stress in the mud eel as evidenced by more accumulation of malondialdehyde (MDA) and hydrogen peroxide (H2O2) during exposure to HEA. Further, hyper-ammonia stress led to significant increase in the levels of mRNA transcripts for inducible hsp70 and hsp90α genes and also their translated proteins in different tissues probably as a consequence of induction of hsp70 and hsp90α genes in the mud eel. However, hyper-ammonia stress was neither associated with any significant alterations in the levels of mRNA transcripts for constitutive hsc70 and hsp90ß genes nor their translated proteins in any of the tissues studied. More abundance of Hsp70 and Hsp90α proteins might be one of the strategies adopted by the mud eel to defend itself from the ammonia-induced cellular damages under ammonia stress. Further, this is the first report of ammonia-induced induction of hsp70 and hsp90α genes under hyper-ammonia stress in any freshwater air-breathing teleost.


Asunto(s)
Amoníaco/toxicidad , Anguilas/genética , Proteínas de Peces/genética , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/genética , Amoníaco/sangre , Amoníaco/farmacocinética , Animales , Anguilas/metabolismo , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , ARN Mensajero/metabolismo , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética
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